<?php
namespace Design\Behavioral\Command;
/**
 * Description
 *
 * PHP version 7
 *
 * @category Custom
 * @package  Custom
 * @author   ryu <mo5467@126.com>
 * @date     2020-04-27 23:54:58
 * @lastTime 2020-04-27 23:56:49
 * @license  https://opensource.org/licenses/MIT MIT License
 * @link     none
 */
interface UndoableCommand extends Command
{


    public function undo() : void;


}//end interface
